当前,无线电引信面临严峻的信息型干扰环境,为保证无线电引信在战场上稳定发挥毁伤效能,抗信息型干扰相关技术成为无线电引信抗干扰领域的研究热点。根据引信干扰机先截获后转发干扰的工作流程,着眼于无线电引信的低截获波束设计,并结...当前,无线电引信面临严峻的信息型干扰环境,为保证无线电引信在战场上稳定发挥毁伤效能,抗信息型干扰相关技术成为无线电引信抗干扰领域的研究热点。根据引信干扰机先截获后转发干扰的工作流程,着眼于无线电引信的低截获波束设计,并结合频控阵(Frequency Diverse Array,FDA)-多输入多输出(Multiple-Input Multiple-Output,MIMO)技术独特的S形弯曲阵列方向图,探索基于FDA-MIMO的无线电引信低截获点状波束设计方法。在分析FDA-MIMO的波束函数后,聚焦于阵元频偏设置对波束合成的影响这一关键点。通过将波峰点与功率下降点设置在较近距离范围Δr内,实现在波峰点附近以Δr为半径的较小邻域内波束幅值较大,而在其他范围波束幅值快速下降的目标,进而运用波束函数解算出各阵元频偏,得到以阵元频偏设置公式为核心的低截获点状波束设计方法。仿真结果表明:在低截获点状波束设计方法的指导下,FDA-MIMO波束在距离维半功率波束宽度为1 m和角度维半功率波束宽度为9°,波束汇聚性能和低截获性能明显好于其他经典频偏设置方法;该设计方法为基于FDA-MIMO的无线电引信低截获波束设计提供了理论支撑,可以提高无线电引信的低截获性能,更好的发挥战场毁伤效能。展开更多
多发多收超宽带雷达能实时探测到目标的距离向和方位向信息,在地质勘测、生命救援、穿墙目标跟踪等领域具有重要的应用价值。该文提出一种基于射频开关切换的伪随机编码超宽带多发多收雷达设计方法,研制出一套伪随机编码超宽带MIMO雷达...多发多收超宽带雷达能实时探测到目标的距离向和方位向信息,在地质勘测、生命救援、穿墙目标跟踪等领域具有重要的应用价值。该文提出一种基于射频开关切换的伪随机编码超宽带多发多收雷达设计方法,研制出一套伪随机编码超宽带MIMO雷达系统。为了降低系统的成本和复杂性,采用射频开关切换的方法来实现多发多收。由于射频开关的耐压值有限,采用峰值功率为18 d Bm的伪随机编码信号作为雷达发射信号。最后通过混合采样方法实现超宽带信号的采样接收,并且调用FPGA内部的DSP硬核来进行实时脉冲压缩,以缓解后续数据处理运算量大的问题。实验结果表明,该雷达系统能实时探测到目标的方位向和距离向信息。展开更多
在军事领域中,机载多输入多输出(multiple input multiple output,MIMO)雷达既要探测机动目标,又要防止被截获接收机侦收。针对这一问题,提出了低截获的单基地非均匀阵列MIMO雷达改进多信号分类(multiple signal classification,MUSIC)...在军事领域中,机载多输入多输出(multiple input multiple output,MIMO)雷达既要探测机动目标,又要防止被截获接收机侦收。针对这一问题,提出了低截获的单基地非均匀阵列MIMO雷达改进多信号分类(multiple signal classification,MUSIC)算法。通过对MIMO雷达匹配滤波后的接收信号进行降维处理、白化处理、时频分析、时频点筛选、正交联合对角化等信号处理,实现了低信噪比(signal to noise ratio,SNR)、低信号持续时间下的方向角估计。研究结果表明,在相同环境下,与MIMO雷达时频MUSIC算法相比,低截获MIMO雷达改进MUSIC算法空间谱指向精度有所提高,可分辨角度差仅为1°的相邻目标,适用SNR降低2 dB且保证了低截获性能。展开更多
Media based modulation(MBM)is expected to be a prominent modulation scheme,which has access to the high data rate by using radio frequency(RF)mirrors and fewer transmit antennas.Associated with multiuser multiple inpu...Media based modulation(MBM)is expected to be a prominent modulation scheme,which has access to the high data rate by using radio frequency(RF)mirrors and fewer transmit antennas.Associated with multiuser multiple input multiple output(MIMO),the MBM scheme achieves better performance than other conventional multiuser MIMO schemes.In this paper,the massive MIMO uplink is considered and a conjunctive MBM transmission scheme for each user is employed.This conjunctive MBM transmission scheme gathers aggregate MBM signals in multiple continuous time slots,which exploits the structured sparsity of these aggregate MBM signals.Under this kind of scenario,a multiuser detector with low complexity based on the compressive sensing(CS)theory to gain better detection performance is proposed.This detector is developed from the greedy sparse recovery technique compressive sampling matching pursuit(CoSaMP)and exploits not only the inherently distributed sparsity of MBM signals but also the structured sparsity of multiple aggregate MBM signals.By exploiting these sparsity,the proposed CoSaMP based multiuser detector achieves reliable detection with low complexity.Simulation results demonstrate that the proposed CoSaMP based multiuser detector achieves better detection performance compared with the conventional methods.展开更多
文摘当前,无线电引信面临严峻的信息型干扰环境,为保证无线电引信在战场上稳定发挥毁伤效能,抗信息型干扰相关技术成为无线电引信抗干扰领域的研究热点。根据引信干扰机先截获后转发干扰的工作流程,着眼于无线电引信的低截获波束设计,并结合频控阵(Frequency Diverse Array,FDA)-多输入多输出(Multiple-Input Multiple-Output,MIMO)技术独特的S形弯曲阵列方向图,探索基于FDA-MIMO的无线电引信低截获点状波束设计方法。在分析FDA-MIMO的波束函数后,聚焦于阵元频偏设置对波束合成的影响这一关键点。通过将波峰点与功率下降点设置在较近距离范围Δr内,实现在波峰点附近以Δr为半径的较小邻域内波束幅值较大,而在其他范围波束幅值快速下降的目标,进而运用波束函数解算出各阵元频偏,得到以阵元频偏设置公式为核心的低截获点状波束设计方法。仿真结果表明:在低截获点状波束设计方法的指导下,FDA-MIMO波束在距离维半功率波束宽度为1 m和角度维半功率波束宽度为9°,波束汇聚性能和低截获性能明显好于其他经典频偏设置方法;该设计方法为基于FDA-MIMO的无线电引信低截获波束设计提供了理论支撑,可以提高无线电引信的低截获性能,更好的发挥战场毁伤效能。
文摘多发多收超宽带雷达能实时探测到目标的距离向和方位向信息,在地质勘测、生命救援、穿墙目标跟踪等领域具有重要的应用价值。该文提出一种基于射频开关切换的伪随机编码超宽带多发多收雷达设计方法,研制出一套伪随机编码超宽带MIMO雷达系统。为了降低系统的成本和复杂性,采用射频开关切换的方法来实现多发多收。由于射频开关的耐压值有限,采用峰值功率为18 d Bm的伪随机编码信号作为雷达发射信号。最后通过混合采样方法实现超宽带信号的采样接收,并且调用FPGA内部的DSP硬核来进行实时脉冲压缩,以缓解后续数据处理运算量大的问题。实验结果表明,该雷达系统能实时探测到目标的方位向和距离向信息。
文摘在军事领域中,机载多输入多输出(multiple input multiple output,MIMO)雷达既要探测机动目标,又要防止被截获接收机侦收。针对这一问题,提出了低截获的单基地非均匀阵列MIMO雷达改进多信号分类(multiple signal classification,MUSIC)算法。通过对MIMO雷达匹配滤波后的接收信号进行降维处理、白化处理、时频分析、时频点筛选、正交联合对角化等信号处理,实现了低信噪比(signal to noise ratio,SNR)、低信号持续时间下的方向角估计。研究结果表明,在相同环境下,与MIMO雷达时频MUSIC算法相比,低截获MIMO雷达改进MUSIC算法空间谱指向精度有所提高,可分辨角度差仅为1°的相邻目标,适用SNR降低2 dB且保证了低截获性能。
文摘Media based modulation(MBM)is expected to be a prominent modulation scheme,which has access to the high data rate by using radio frequency(RF)mirrors and fewer transmit antennas.Associated with multiuser multiple input multiple output(MIMO),the MBM scheme achieves better performance than other conventional multiuser MIMO schemes.In this paper,the massive MIMO uplink is considered and a conjunctive MBM transmission scheme for each user is employed.This conjunctive MBM transmission scheme gathers aggregate MBM signals in multiple continuous time slots,which exploits the structured sparsity of these aggregate MBM signals.Under this kind of scenario,a multiuser detector with low complexity based on the compressive sensing(CS)theory to gain better detection performance is proposed.This detector is developed from the greedy sparse recovery technique compressive sampling matching pursuit(CoSaMP)and exploits not only the inherently distributed sparsity of MBM signals but also the structured sparsity of multiple aggregate MBM signals.By exploiting these sparsity,the proposed CoSaMP based multiuser detector achieves reliable detection with low complexity.Simulation results demonstrate that the proposed CoSaMP based multiuser detector achieves better detection performance compared with the conventional methods.
